The present invention pertains to an axially symmetrical apparatus intended to separate one annular chamber filled with a fluid placed under high pressure from another coaxial annular chamber containing the same fluid under low pressure, with motion being imparted to the walls of said chambers.
This type of arrangement is especially applicable for fluid pumps with vertical shafts, and particularly for pressurized water pumps.
Hydrostatic joint arrangements providing pressure seals in pressurized water pumps, for example, for controlled releasing of fluid are not uncommon. For example, French Pat. Nos. 1,422,767, 1,435,568, or 1,459,107 describe several versions of such arrangements. Usually, the aforementioned arrangements include a metal bearing attached to the shaft, with the upper portion of the bearing ring (hereinafter referred to as a "bearing") forming a wall upon which the bottom portion of a floating ring (hereinafter referred to as a "float") can rest, thereby forming a pressure seal. The float can move in an axial direction, and its surface possesses a shape which permits a minimum flow of fluid between the float and the metal bearing to furnish sufficient force to ensure gradual lifting of the float during operation, in such a manner as to prevent damage to components such as the bearing situated opposite the float, while also providing a pressure seal between the two chambers filled with fluid.
Nevertheless, the aforementioned arrangements are characterized by two fundamental disadvantages. On the one hand, any decrease in fluid pressure inside the high pressure chamber can cause the components forming the pressure seal to be affected by wear and tear. On the other hand, the outlet for the fluid which is formed by the oppositely situated components constituting the pressure seal displays a tendency to become clogged, as a result of particles transported within the fluid.
The purpose of the present invention is to overcome these disadvantages without significantly changing the general structure of the aforementioned hydrostatic arrangement.